13 дек. 2015 г. 12:53 пользователь "Daniel P. Berrange" <<a href="mailto:berrange@redhat.com">berrange@redhat.com</a>> написал: > > The VIR_DOMAIN_STATS_VCPU flag to virDomainListGetStats > enables reporting of stats about vCPUs. Currently we > only report the cumulative CPU running time and the > execution state. > > This adds reporting of the wait time - time the vCPU > wants to run, but the host schedular has something else > running ahead of it. > As i understand this is well known steal time analog that can be viewed inside vm? > The data is reported per-vCPU eg > > $ virsh domstats --vcpu demo > Domain: 'demo' > vcpu.current=4 > vcpu.maximum=4 > vcpu.0.state=1 > vcpu.0.time=1420000000 > vcpu.0.wait=18403928 > vcpu.1.state=1 > vcpu.1.time=130000000 > vcpu.1.wait=10612111 > vcpu.2.state=1 > vcpu.2.time=110000000 > vcpu.2.wait=12759501 > vcpu.3.state=1 > vcpu.3.time=90000000 > vcpu.3.wait=21825087 > > In implementing this I notice our reporting of CPU execute > time has very poor granularity, since we are getting it > from /proc/$PID/stat. As a future enhancement we should > prefer to get CPU execute time from /proc/$PID/schedstat > or /proc/$PID/sched (if either exist on the running kernel) > > Signed-off-by: Daniel P. Berrange <<a href="mailto:berrange@redhat.com">berrange@redhat.com</a>> > --- > src/qemu/qemu_driver.c | 100 +++++++++++++++++++++++++++++++++++++++++++++++-- > 1 file changed, 96 insertions(+), 4 deletions(-) > > diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c > index 783a7cd..5293294 100644 > --- a/src/qemu/qemu_driver.c > +++ b/src/qemu/qemu_driver.c > @@ -1361,6 +1361,80 @@ static char *qemuConnectGetCapabilities(virConnectPtr conn) { > > > static int > +qemuGetSchedInfo(unsigned long long *cpuWait, > + pid_t pid, pid_t tid) > +{ > + char *proc = NULL; > + char *data = NULL; > + char **lines = NULL; > + size_t i; > + int ret = -1; > + double val; > + > + *cpuWait = 0; > + > + /* In general, we cannot assume pid_t fits in int; but /proc parsing > + * is specific to Linux where int works fine. */ > + if (tid) > + ret = virAsprintf(&proc, "/proc/%d/task/%d/sched", (int)pid, (int)tid); > + else > + ret = virAsprintf(&proc, "/proc/%d/sched", (int)pid); > + if (ret < 0) > + goto cleanup; > + > + /* The file is not guaranteed to exist (needs CONFIG_SCHED_DEBUG) */ > + if (access(proc, R_OK) < 0) > + return 0; > + > + if (virFileReadAll(proc, (1<<16), &data) < 0) > + goto cleanup; > + > + lines = virStringSplit(data, "\n", 0); > + if (!lines) > + goto cleanup; > + > + for (i = 0; lines[i] != NULL; i++) { > + const char *line = lines[i]; > + > + /* Needs CONFIG_SCHEDSTATS. The second check > + * is the old name the kernel used in past */ > + if (STRPREFIX(line, "se.statistics.wait_sum") || > + STRPREFIX(line, "se.wait_sum")) { > + line = strchr(line, ':'); > + if (!line) { > + virReportError(VIR_ERR_INTERNAL_ERROR, > + _("Missing separate in sched info '%s'"), > + lines[i]); > + goto cleanup; > + } > + line++; > + while (*line == ' ') { > + line++; > + } > + > + if (virStrToDouble(line, NULL, &val) < 0) { > + virReportError(VIR_ERR_INTERNAL_ERROR, > + _("Unable to parse sched info value '%s'"), > + line); > + goto cleanup; > + } > + > + *cpuWait = (unsigned long long)(val * 1000000); > + break; > + } > + } > + > + ret = 0; > + > + cleanup: > + VIR_FREE(data); > + VIR_FREE(proc); > + VIR_FREE(lines); > + return ret; > +} > + > + > +static int > qemuGetProcessInfo(unsigned long long *cpuTime, int *lastCpu, long *vm_rss, > pid_t pid, int tid) > { > @@ -1424,6 +1498,7 @@ qemuGetProcessInfo(unsigned long long *cpuTime, int *lastCpu, long *vm_rss, > static int > qemuDomainHelperGetVcpus(virDomainObjPtr vm, > virVcpuInfoPtr info, > + unsigned long long *cpuwait, > int maxinfo, > unsigned char *cpumaps, > int maplen) > @@ -1476,6 +1551,11 @@ qemuDomainHelperGetVcpus(virDomainObjPtr vm, > virBitmapFree(map); > } > > + if (cpuwait) { > + if (qemuGetSchedInfo(&(cpuwait[i]), vm->pid, vcpupid) < 0) > + return -1; > + } > + > ncpuinfo++; > } > > @@ -5517,7 +5597,7 @@ qemuDomainGetVcpus(virDomainPtr dom, > goto cleanup; > } > > - ret = qemuDomainHelperGetVcpus(vm, info, maxinfo, cpumaps, maplen); > + ret = qemuDomainHelperGetVcpus(vm, info, NULL, maxinfo, cpumaps, maplen); > > cleanup: > virDomainObjEndAPI(&vm); > @@ -19089,6 +19169,7 @@ qemuDomainGetStatsVcpu(virQEMUDriverPtr driver ATTRIBUTE_UNUSED, > int ret = -1; > char param_name[VIR_TYPED_PARAM_FIELD_LENGTH]; > virVcpuInfoPtr cpuinfo = NULL; > + unsigned long long *cpuwait = NULL; > > if (virTypedParamsAddUInt(&record->params, > &record->nparams, > @@ -19104,10 +19185,12 @@ qemuDomainGetStatsVcpu(virQEMUDriverPtr driver ATTRIBUTE_UNUSED, > virDomainDefGetVcpusMax(dom->def)) < 0) > return -1; > > - if (VIR_ALLOC_N(cpuinfo, virDomainDefGetVcpus(dom->def)) < 0) > - return -1; > + if (VIR_ALLOC_N(cpuinfo, virDomainDefGetVcpus(dom->def)) < 0 || > + VIR_ALLOC_N(cpuwait, virDomainDefGetVcpus(dom->def)) < 0) > + goto cleanup; > > - if (qemuDomainHelperGetVcpus(dom, cpuinfo, virDomainDefGetVcpus(dom->def), > + if (qemuDomainHelperGetVcpus(dom, cpuinfo, cpuwait, > + virDomainDefGetVcpus(dom->def), > NULL, 0) < 0) { > virResetLastError(); > ret = 0; /* it's ok to be silent and go ahead */ > @@ -19136,12 +19219,21 @@ qemuDomainGetStatsVcpu(virQEMUDriverPtr driver ATTRIBUTE_UNUSED, > param_name, > cpuinfo[i].cpuTime) < 0) > goto cleanup; > + snprintf(param_name, VIR_TYPED_PARAM_FIELD_LENGTH, > + "vcpu.%zu.wait", i); > + if (virTypedParamsAddULLong(&record->params, > + &record->nparams, > + maxparams, > + param_name, > + cpuwait[i]) < 0) > + goto cleanup; > } > > ret = 0; > > cleanup: > VIR_FREE(cpuinfo); > + VIR_FREE(cpuwait); > return ret; > } > > -- > 2.5.0 > > -- > libvir-list mailing list > <a href="mailto:libvir-list@redhat.com">libvir-list@redhat.com</a> > <a href="https://www.redhat.com/mailman/listinfo/libvir-list">https://www.redhat.com/mailman/listinfo/libvir-list</a>